ogrodbcdatasource.cpp

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                papszGeomCol = 
                    CSLAddString( papszGeomCol, oStmt.GetColData(1) );
            }
        }
    }
            
/* -------------------------------------------------------------------- */
/*      Otherwise our final resort is to return all tables as           */
/*      non-spatial tables.                                             */
/* -------------------------------------------------------------------- */
    if( papszTables == NULL )
    {
        CPLODBCStatement oTableList( &oSession );
        
        if( oTableList.GetTables() )
        {
            while( oTableList.Fetch() )
            {
                papszTables = 
                    CSLAddString( papszTables, oTableList.GetColData(2) );
                papszGeomCol = CSLAddString(papszGeomCol,"");
            }
        }
    }

/* -------------------------------------------------------------------- */
/*      If we have an explicit list of requested tables, use them       */
/*      (non-spatial).                                                  */
/* -------------------------------------------------------------------- */
    for( int iTable = 0; 
         papszTables != NULL && papszTables[iTable] != NULL; 
         iTable++ )
    {
        if( strlen(papszGeomCol[iTable]) > 0 )
            OpenTable( papszTables[iTable], papszGeomCol[iTable], bUpdate );
        else
            OpenTable( papszTables[iTable], NULL, bUpdate );
    }

    CSLDestroy( papszTables );
    CSLDestroy( papszGeomCol );

/* -------------------------------------------------------------------- */
/*      If no explicit list of tables was given, check for a list in    */
/*      a geometry_columns table.                                       */
/* -------------------------------------------------------------------- */
    if ( pszSRSTableName )
    {
        CPLODBCStatement oSRSList( &oSession );

        if ( !pszSRTextCol )
            pszSRTextCol = CPLStrdup( "srtext" );
        if ( !pszSRIDCol )
            pszSRIDCol = CPLStrdup( "srid" );

        oSRSList.Append( "SELECT " );
        oSRSList.Append( pszSRIDCol );
        oSRSList.Append( "," );
        oSRSList.Append( pszSRTextCol );
        oSRSList.Append( " FROM " );
        oSRSList.Append( pszSRSTableName );

        CPLDebug( "OGR_ODBC", "ExecuteSQL(%s) to read SRS table",
                  oSRSList.GetCommand() );
        if ( oSRSList.ExecuteSQL() )
        {
            int nRows = 256;     // A reasonable number of SRIDs to start from
            panSRID = (int *)CPLMalloc( nRows * sizeof(int) );
            papoSRS = (OGRSpatialReference **)
                CPLMalloc( nRows * sizeof(OGRSpatialReference*) );

            while ( oSRSList.Fetch() )
            {
                char *pszSRID = (char *) oSRSList.GetColData( pszSRIDCol );
                if ( !pszSRID )
                    continue;

                char *pszSRText = (char *) oSRSList.GetColData( pszSRTextCol );

                if ( pszSRText )
                {
                    if ( nKnownSRID > nRows )
                    {
                        nRows *= 2;
                        panSRID = (int *)CPLRealloc( panSRID,
                                                     nRows * sizeof(int) );
                        papoSRS = (OGRSpatialReference **)
                            CPLRealloc( papoSRS,
                            nRows * sizeof(OGRSpatialReference*) );
                    }
                    panSRID[nKnownSRID] = atoi( pszSRID );
                    papoSRS[nKnownSRID] = new OGRSpatialReference();
                    if ( papoSRS[nKnownSRID]->importFromWkt( &pszSRText )
                         != OGRERR_NONE )
                    {
                        delete papoSRS[nKnownSRID];
                        continue;
                    }
                    nKnownSRID++;
                }
            }
        }
    }

    if ( pszSRIDCol )
        CPLFree( pszSRIDCol );
    if ( pszSRTextCol )
        CPLFree( pszSRTextCol );
    if ( pszSRSTableName )
        CPLFree( pszSRSTableName );

    return TRUE;
}

/************************************************************************/
/*                             OpenTable()                              */
/************************************************************************/

int OGRODBCDataSource::OpenTable( const char *pszNewName, 
                                  const char *pszGeomCol,
                                  int bUpdate )

{
/* -------------------------------------------------------------------- */
/*      Create the layer object.                                        */
/* -------------------------------------------------------------------- */
    OGRODBCTableLayer  *poLayer;

    poLayer = new OGRODBCTableLayer( this );

    if( poLayer->Initialize( pszNewName, pszGeomCol ) )
    {
        delete poLayer;
        return FALSE;
    }

/* -------------------------------------------------------------------- */
/*      Add layer to data source layer list.                            */
/* -------------------------------------------------------------------- */
    papoLayers = (OGRODBCLayer **)
        CPLRealloc( papoLayers,  sizeof(OGRODBCLayer *) * (nLayers+1) );
    papoLayers[nLayers++] = poLayer;
    
    return TRUE;
}

/************************************************************************/
/*                           TestCapability()                           */
/************************************************************************/

int OGRODBCDataSource::TestCapability( const char * pszCap )

{
    if( EQUAL(pszCap,ODsCCreateLayer) )
        return TRUE;
    else
        return FALSE;
}

/************************************************************************/
/*                              GetLayer()                              */
/************************************************************************/

OGRLayer *OGRODBCDataSource::GetLayer( int iLayer )

{
    if( iLayer < 0 || iLayer >= nLayers )
        return NULL;
    else
        return papoLayers[iLayer];
}
/************************************************************************/
/*                             ExecuteSQL()                             */
/************************************************************************/

OGRLayer * OGRODBCDataSource::ExecuteSQL( const char *pszSQLCommand,
                                          OGRGeometry *poSpatialFilter,
                                          const char *pszDialect )

{
/* -------------------------------------------------------------------- */
/*      Use generic imlplementation for OGRSQL dialect.                 */
/* -------------------------------------------------------------------- */
    if( pszDialect != NULL && EQUAL(pszDialect,"OGRSQL") )
        return OGRDataSource::ExecuteSQL( pszSQLCommand, 
                                          poSpatialFilter, 
                                          pszDialect );

/* -------------------------------------------------------------------- */
/*      Execute statement.                                              */
/* -------------------------------------------------------------------- */
    CPLODBCStatement *poStmt = new CPLODBCStatement( &oSession );

    poStmt->Append( pszSQLCommand );
    if( !poStmt->ExecuteSQL() )
    {
        CPLError( CE_Failure, CPLE_AppDefined, 
                  "%s", oSession.GetLastError() );
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Are there result columns for this statement?                    */
/* -------------------------------------------------------------------- */
    if( poStmt->GetColCount() == 0 )
    {
        delete poStmt;
        CPLErrorReset();
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Create a results layer.  It will take ownership of the          */
/*      statement.                                                      */
/* -------------------------------------------------------------------- */
    OGRODBCSelectLayer *poLayer = NULL;
        
    poLayer = new OGRODBCSelectLayer( this, poStmt );

    if( poSpatialFilter != NULL )
        poLayer->SetSpatialFilter( poSpatialFilter );
    
    return poLayer;
}

/************************************************************************/
/*                          ReleaseResultSet()                          */
/************************************************************************/

void OGRODBCDataSource::ReleaseResultSet( OGRLayer * poLayer )

{
    delete poLayer;
}